Apparatus including a sucker with autoselection function for handling material

ABSTRACT

An apparatus for handling material of the type in sheets or portions of flat sheets, includes at least one device with an autoselection function for the lifting-release of the material, of the type with a vacuum that is obtained between the sucker and the material, by a vacuum forming device through the Venturi effect or by means of a vacuum pump. This apparatus is made up of a multi-way pneumatic supply circuit of an auto-selection and auto-relief valve that includes principal pneumatic commutators. The commutators are interconnected to a third commutator that is interposed between the vacuum forming device and the auto-selection valve that supplies the sucker.

RELATED U.S. APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO MICROFICHE APPENDIX

Not applicable.

FIELD OF THE INVENTION

This invention refers to an apparatus including at least one sucker,with a vacuum obtained by means of the Venturi effect or by means of avacuum pump, with an auto-selection function for handling material ofthe type in sheets or objects that lend themselves to being handled withthis system.

The invention finds particular application where the vacuum is usednon-exclusively in the metal plate moving sectors.

BACKGROUND OF THE INVENTION

In the field of industrial automations, for example, installationsworking <<unmanned>> or “lights off”, namely without human presence, theinvention assumes particular interest.

One of the characteristics that distinguishes said installations, is thefact that each installation is prepared during day hours for functioningwithout human presence during nocturnal hours.

A typical case is illustrated by the installations in which automaticsystems are provided for loading, on the construction line, andunloading of materials to be submitted to processing, such as metalsheets, plastic material plates, ceramic and glass, with the aim ofallowing processing to be carried out continuously without the need tointervene at the end of every operative cycle. Said systems, forexample, are required in sheet cutting installations, those employinglaser or plasma techniques, oxygen cutting, water techniques and alsoothers.

Generally, therefore, it is possible to consider that this concernsinstallations subdivided into at least two working areas, respectivelyan upstream unit, including the group loader-feeder of the material insheets, an intermediate station, for instance made up of the cuttingapparatus, and a possible downstream adjacent unit including astacker-ejector of the sheet processed in this way.

With respect to these installations, certain drawbacks have beenobserved by operators in this sector, above all with reference to themost common grill or bench material loading systems in the intermediatestation.

Among the most well-know systems, proposed for loading and unloading thesheeting, for example using a cutting apparatus grill or a bench for afolding press, it is possible to cite substantially five techniques.

The first of the four, the primary technique is known for manual removalof pieces cut from a grill or bench with the subsequent loading of thenew sheet, by means of an overhead crane, fork truck, purchase block orsucker frame mounted on a fixed oscillating arm.

A second solution consists in providing two grills or benches, operatingon the cutting or processing installation, in such a way as to beoperated alternatively on a grill for loading and unloading, while theother is functioning. A third solution, for sheet cutting installations,is intended to optimize the system which in the previous point provideda carousel with a certain number of grills, collected in a verticalwarehouse.

A fourth solution, suitable for interacting with one of the systemsdescribed previously with respect to the unloading of the grill,provides a vertical warehouse upstream of the cutting unit, with moreshelves, where the sheets to be processed are pre-arranged, in such away that, according to the program, an extractor or handler with suckerscan pick up and transfer the material on the grill of the intermediateunit so it can be processed.

Prior Art

Therefore, suckers are known the in the field of assistance for machinetools and in other sectors, which, supported by conventional systems,are made to adhere the peripheral border of the circular flange to theflat surface of the underlying material to be handled. Once placed incontact, a temporary depression is produced, substantially, which causesthe material to remain in contact with said suckers. In this way thesuckers, raising themselves from the support base of the material, willdetermine the subsequent transfer of the material to an adjacentstation. Once placed in the release position, a device provides there-balancing of the pressure on the interior of the cups of the suckers,allowing the detachment of the material. It is therefore evident giventhat said suckers are connected to systems that allow depressiongeneration and re-balancing of the sucker once certain conditions havebeen reached. More particularly, said devices utilize the Venturi effector in some cases a common vacuum pump.

Therefore, for example in U.S. Pat. No. 5,979,889 (Klopfenstein), apractical application of the Venturi effect for generating a depressionin the sucker cup is described. In detail, the sucker is mounted withthe tubular connector along a main rod that is channelled to intersectit on the bias. A second connector is coaxial to the main channelled rodand develops until passing beyond the interconnection point with thetubular pin. In this way, by introducing a fluid through the secondconnector, the air present in the cup in contact with the material issucked again, so that the sucker remains in very close contact oradhered to the surface of the material to be handled.

Also U.S. Pat. No. 5,928,537 (Fortune) describes a system that uses theVenturi effect to generate a vacuum on the interior of a sucker. In moredetail, a tool for lifting small portions of materials is proposed,which is provided on one side with a sucker and is connected on theother side to a vacuum generator. Said vacuum generator is connected onone side to a first ON/OFF valve that allows the emission of compressedair and on the other side, downstream of the circuit, to a second valvethat connects with the exterior. Operating with the first valve in openposition, the compressed airflow crosses the vacuum generator that is incontact by means of a connector with the tool provided with a sucker.The compressed airflow finds a vent in a downstream position set apartwith respect to the tool's connector and continues through the secondvalve in open position. In this way, the necessary re-suction isproduced along the tool's connector, so that the sucker remains in theposition of being adhered to the material. Operating inversely, thusclosing the second valve, which is downstream of the circuit, thecompressed airflow passes across the tool's connector and thereforere-balances the pressure on the interior of the cup obtaining thedetachment of the material.

State of the Art Most Similar to the Invention

U.S. Pat. No. 4,750,768 (Kumar), describes an adhering device. Thissubstantially concerns a pneumatic vacuum generator that uses an ampfluid sensor that senses the presence of an object when said object isin contact with the sucker cup. This circumstance activates the mainVenturi effect vacuum generator that provides for forming the vacuumnecessary that makes it possible for the object to be lifted. Anexternal release signal determines the arrest of the vacuum to releasethe object. The energy for the vacuum, in this case, is to be generatedonly when the object is lifted, in such a way as to suppress energyconsumption and noise. Furthermore, it is possible to adjust the levelof force necessary for lifting. The fluid logic circuit, automaticallyblocks the vacuum in the sucker, while the supply to the main Venturi isplaced in the OFF position after a pre-established period of time.

U.S. Pat. No. 5,795,001 (Burke) describes a device for manipulatingarticles. The small hand contains a sucker that cooperates with acircuit that includes an electric motor coupled to a vacuum pump. Anelectronic circuit allows the operator to control directly theapplication of vacuum to the sucker. Furthermore, an electronic circuitdetects the prolonged vacuum between the sucker and the object to behandled and if this reaches a predetermined low level, the electroniccircuit informs the operator of the condition and automaticallyre-starts the motor of the vacuum pump until the depression level isre-established. An alternative solution to this invention provides for aVenturi effect vacuum generator that can substitute directly the modulethat includes the vacuum pump.

In conclusion it is correct to affirm that at present it is known thatfor the formation of the vacuum in said suckers, a Venturi for eachsucker or a Venturi for several suckers is applied, and if a depressiongreater than that which can be generated by a Venturi was necessary, itis possible to resort to a vacuum pump that, also in this case, can beapplied to one or several suckers.

Drawbacks

In terms of the systems described with the Venturi effect, these presentan economical advantage and are simple to apply. For example, in thecase of the use of several suckers and one Venturi for each of these, itis guaranteed that if one or several suckers does not completely adhereto the object, the depression in the other suckers is maintained, thusensuring the lifting or transportation of the piece. In this case it isevident that the suckers that are not able to create the vacuum continueto be supplied thus giving rise to the wastage of compressed air. Tocompensate for the air loss problem, manual taps can be applied thatblock the Venturi supply of the sucker to be excluded. However, it isevident that this solution appears inconvenient since manualintervention is required. From a practical point of view, thiscircumstance involves the stoppage of the installation causing increaseddown times, in one case, it can require processing on flat materialpieces that often present different dimensions or are not perfectlyaligned and coplanar.

Others systems, to avoid the air loss problem and to manage the valvesmanually, provide the application of electro-valves. These systemsinvolve the use of management software, of electric wiring or, in themore economic version, a series of switches. From a practical point ofview, the proposal causes considerable complexity in the installationswith the relative implementation and maintenance costs. However, to thiscan be added the fact that the proper positioning of the piece to belifted is necessary in order to avoid the useless supply to the suckersthat are not involved.

In the case in which, unlike the Venturi system, it is possible to optfor an installation with a vacuum pump, or with a Venturi for the entireinstallation, it is necessary to define from the start of processing thesuckers that activate the adhering function and those that do not. Inthis hypothesis, in the event that a good adherence is not provided orthe sucker detaches, it would cause the depression to decline in theentire installation, thus provoking the detachment of the object fromthe other suckers (and eventually the stoppage of the installation).

Other systems, not mentioned previously include a relief valve wheregiven the possible unsuccessful adherence of the object, the aspiratedairflow will close the passage thus eliminating the vacuum supply. It isthe opinion of the applicant that this system is not reliable, since itrequires an ample aspiration flow in order for the device to in turn beable to stop the it. In a second system a small hole would alwaysremain, through which air from the exterior continues to be sucked, thusit is not airtight.

Here there is the need for the companies to determine alternative andmore effective systems not including those described previously.

One aim of this invention is also to avoid the above-mentioneddrawbacks.

BRIEF SUMMARY OF THE INVENTION

This and other aims are reached with this invention according to thecharacteristics as in the included claims, solving the arising problems,by means of an apparatus for handling material of the type in sheets orportions of flat sheets, including at least one device with anautoselection function for the lifting-release of the material, of thetype with a vacuum that is obtained between the sucker and the material,by vacuum forming means through the Venturi effect or by means of avacuum pump; this apparatus is made up of a multi-way pneumatic supplycircuit of an auto-selection and auto-relief valve that includesprincipal pneumatic commutators, said commutators being interconnectedto a third commutator that is interposed between the vacuum formingmeans and the auto-selection valve that supplies the sucker.

Aims of the Invention

The considerable creative contribution, verified in the proposal nowdescribed, constitutes an immediate technical progress in order toobtain different advantages.

First of all, one aim consists in conferring additional safety to thesystem described. The principle is based substantially on the autoreliefof the formation of the vacuum created in the sucker, so that in aseries of suckers those that are not adhered are excluded automatically.For example, in the event that in an installation a sucker is positionedclose to the edge of the piece to be raised (ref. FIG. 13) and thusexperiences a small loss of air, causing the detachment of theadherence, the vacuum is aspirated through this sucker and also servesto reduce the depression in the other suckers thus letting the piecefall (if the installation has the Venturi effect or a centralized vacuumpump). With the above-described system this situation would not occursince the sucker in adherence would automatically be excluded withoutcompromising the proper functioning of the others. From a practicalpoint of view, consequently, operator intervention and control as wellas the use of complex management software would be avoided, providingthe installation with particular inexpensiveness and reliability.Therefore, almost no maintenance with the implied costs is required,relative to the construction and the installations, rather thancontents.

A further aim consists in considering a notable saving of energy, bothbecause the suckers not involved in the lifting exclude themselvesautomatically as well as because air consumption is suppressed since thesupply is not required until the sucker is maintained within the valuesof the established depression.

These advantages have the quite relevant value of producing apparatuswith a good technological, multi-functional and extremely reliablecontent, even if submitted to particular working loads.

Others advantages will appear from the following specific description ofsome preferred embodiments, with the aid of the enclosed schematicdrawings, whose implementation details are not to be consideredlimitative, but only illustrative.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a diagram of the apparatus that is the object of thisinvention in the rest position, which represents a plan of the pneumaticinstallation for the supply of the autoselection valve and of the suckerconnected to it, cooperating with a Venturi effect vacuum generator, aswell as the connecting circuit between them.

FIG. 2 is a diagram of the apparatus that is the object of thisinvention as in FIG. 1, in active position.

FIG. 3 is a diagram of the apparatus that is the object of thisinvention, as in previous Figures in auto-relief position.

FIG. 4 is a diagram of the apparatus that is the object of thisinvention, as in previous Figures in stand by/economy position.

FIG. 5 is a diagram of the apparatus that is the object of thisinvention, as in previous Figures in a position of depression loss inthe sucker.

FIG. 6 is a diagram of the apparatus that is the object of thisinvention, as in previous Figures in a depression reactivation position.

FIG. 7 is a diagram of the apparatus that is the object of thisinvention, as in previous Figures in a position of detachment from thepiece.

FIG. 8 is a diagram of the apparatus that is the object of thisinvention in the rest position, that represents a plan of the pneumaticinstallation for supplying the autoselection valve and sucker connectedto it, cooperating with a vacuum pump, as well as the connecting circuitbetween the them.

FIG. 9 is a diagram of the apparatus that is the object of thisinvention in rest position, that represents one variant of the plan ofthe pneumatic installation for supplying the auto-selection valve andsucker connected to it, cooperating with a Venturi effect vacuumgenerator, as well as the connecting circuit between them.

FIG. 10 is a diagram of an apparatus with several suckers, supplied by avacuum pump.

FIG. 11 is a diagram of an apparatus with several suckers, supplied by asingle Venturi effect vacuum generator.

FIG. 12 is a diagram of an apparatus with several suckers, supplied by acorresponding number of Venturi effect vacuum generators.

FIG. 13 is an illustrative plan of certain possible sucker workingpositions.

DETAILED DESCRIPTION OF THE INVENTION

With reference also to the Figures, it is observed that in aninstallation for handling/lifting of flat material, for example, insheets or pieces of sheet M, an apparatus S1, S2 is provided thatincludes at least one sucker 1 on the interior of which, when adhered incorrespondence to the material M, is to form the vacuum.

More particularly, the apparatus S1, S2 can be divided into threeblocks, respectively A, B and B1 to which at least one sucker isconnected I. The block A is made up of a pneumatic installation forsupplying the blocks B-B1, which are made up respectively of anauto-selector valve that cooperates with means to generate the vacuumF1, F2. In this case, said means for generating the vacuum can include asolution with Venturi effect F1 or a vacuum pump F2.

The block A, is essentially made up of: A pressure regulator 1.1 A firstrotary converter electro-valve 1 A pressure regulator 2.1 A secondrotary converter electro-valve 2 A pressure regulator 3.1 A third rotaryconverter electro-valve 3 An alternative valve 4

In terms of the second and third block B-B1, that includes theauto-selection valve, it is substantially made up of: A first pneumaticcommutator C A second pneumatic commutator D A third pneumaticcommutator F A relief valve G A vacuum generator F1, F2 Portions of thevalves groups C, D, E 0,1 high 0,0 low

As a rule, while the block A serves to supply one or several suckers 1,the block B-B1 can be applied to every sucker or group of suckersaccording to the needs of the installation.

Apparatus Activation Phase

In FIG. 2 the activation of the circuit of the auto-selection valve(V.A.S.) through a compressed air impulse is represented. This impulseoccurs through the excitation of valve 1 and 2 of block A. In terms ofthe impulse of the air conferred from the electro-valve 1 it is observedthat, passing through the pneumatic commutator C, D and E, it isintended to supply the Venturi effect vacuum generator F1. On thecontrary, the airflow, whose concurrence is provided by an impulse fromthe electro-valve 2, will supply the pneumatic commutator D in such away as to establish the movement of the piston D1 in the position 0.1.More particularly, the air originating from the electro-valve 2, passingthrough the alternative valve 4, moves the sphere 4.1 to position (b),allowing the supply of the circuit P1, which on entering block Bdetermines the movement of said piston D1 in position 0.1 for theduration of the pulse.

In terms of airflow originating from the electro-valve 1 entering intothe block B-B1 through the circuit P, it is observed that this willsupply the Venturi F1 and open the relief valve G to activate adepression in the circuit L and therefore maintain the piston D1 inauto-relief position (0.1) maintaining this position only if the suckerI is well positioned.

The block B-B1 forms part of a third pneumatic commutator E that isconnected to said circuit P1 and P. In this position said commutator Edoes not move, as it requires higher pressure since it is provided witha more rigid spring E2.

Consequently, the airflow introduced by the electro-valve 1, along thecircuit P passes first across the pneumatic commutator C and D, thenacross the commutator E to supply the Venturi effect vacuum generatorF1. The Venturi F1 forms the vacuum that will thus lift the sphere ofthe relief valve G in this way supplying the circuit L with a depressionthat will simultaneously supply the sucker I for the movement of thematerial M and the piloting of the circuit L. The depression of thepiloting on circuit L, passing through the perforations D3 of the shaftof the piston D1, forms an eddy in the upper chamber of the commutator Dmaintaining the piston D1 in position 0.1, forming an auto-reliefcircuit. The depression created in the circuit L involves one or moresuckers I. The suckers, adhered to the piece to be moved, even in theevent of a small intake of air from the exterior, cause a rapiddepression increase in the circuit L until tripping the auto-reliefphase of the system (piston D1).

Apparatus Autorelief Phase

(Ref. FIG. 3) At the point when the vacuum has reached a sufficientdepression value to maintain the piston D1 in position 0.1 theelectro-valve 2 of the block A is to be de-excited. To maintain itselfin this position a minimum depression is sufficient; this allows theinstallation to remain primed even if there are tolerable losses on thesuckers themselves. The detainment of the piston D1 in position 0.1takes place through the depression of the circuit L transmitted acrossthe perforation D3 in the shaft of the piston D1, (that is normallyfound in position 0.0 pushed by the spring D2) which is held in position0.1 until the sucker(s) I maintains a tolerable depression hold on thematerial M. If the sucker I should suffer a heavy loss due toperforations and positioning close to the edge of the material M orcompletely outside of the latter, by automatically de-exciting theelectro-valve 2 of block A, the supply of the Venturi F1 is interrupted.The interruption of the supply of the Venturi F1 can also take place ifthe sucker I separates from the material M, thus interrupting theauto-relief of piston D1 by blocking the flow and eliminating uselessair consumption.

Apparatus Stand-By Economy Phase

(Ref. FIG. 4) The depression to be created will continue to increaseuntil reaching the maximum allowed or pre-established. At this point,the piston C1 equipped with a spring C2 (adjustable) sturdier than thespring D2 of the commutator D will be placed in position 0.1subsequently (reaching the maximum or established depression allowed)with respect to the commutator D. The movement of the piston C1 of thecommutator C in position 0.1 will interrupt the airflow originating fromthe electro-valve 1 of the block A, destined to supply the Venturi F1.In this way, useless air consumption is avoided, while the circuit L inmaximum depression, will maintain the sucker I in adherence on thematerial M and this thanks to the tightness of the relief valve G.

Intervention Phase in Case of Depression Loss

(Ref. FIG. 5) If the depression of the circuit L, due to small losses,should fall below the maintenance value in position 0.1 of the piston C1of the commutator C, placing itself in position 0.0, the airfloworiginating from the electro-valve 1 of the block A will supply thecommutator D in position 0.1 which in turn, through the commutator E,will supply the Venturi effect vacuum generator F1. The latter, creatingthe depression flow again, re-opens the relief valve G.

Reactivated Depression Phase

(Ref. FIG. 6) On re-opening the relief valve G the depression value ofthe circuit L returns to the maximum, thus re-positioning the piston C1of the commutator C to auto-relief in position 0.1 and in this wayre-closing the compressed airflow originating from the electro-valve 1of the block A with the similar closure of the relief valve G.

Detachment Phase of Sucker I From Material M

(Ref. FIG. 7) The detachment of the sucker I from the material M takesplace while continuing to keep electro-valve 1 of the block A excitedand exciting the electro-valve 3 which causes a higher air pressure toflow through circuit P1 than that which flows through the electro-valve2, in this way moving the sphere 4.1 of the alternative valve 4 intoposition (a). The air with a higher pressure than that exerted for theactivation of the system for the adherence of the sheet will maintainthe piston D1 of the commutator D in position 0.1, moreover it will movethe cursor E1 of the commutator E into position 0.0, thus blocking thesupply of the Venturi effect vacuum generator F1 means, bypassing theairflow directly to the circuit L to the sucker I. The latter, onreceiving the blast of compressed air, rather than a depression, willdetach from the material M rapidly, subsequently the entire system willremain in an apparatus rest position (ref. FIG. 1) to be ready foranother cycle.

The apparatus described above can be utilized even without vacuumgenerator means of the type with Venturi effect F1. In this case,instead of supplying the apparatus through the line P with air pressure,it can be supplied directly by a vacuum pump (ref. FIG. 8), or from asingle vacuum generator of the type with Venturi effect (FIG. 9), bothwith dimensions for consumption proportional to the number of suckersemployed. The difference with respect to the description of previousfunctioning (a vacuum generator of the type with Venturi effect for eachauto-selection valve) consists in supplying the line P for the suckerdetachment phase with a pressurized airflow, exciting the electro-valve1 and de-exciting the electro-valve 5, when for all the other previousphases it is supplied by a line in depression rather under pressure.

1. Apparatus for handling material, comprising: at least one sucker forlifting-release of the material, providing a vacuum, obtained betweensaid sucker and the material to be handled, generated by vacuum formingmeans by means of Venturi effect or by a vacuum pump; and a multi-waypneumatic circuit of an auto-selection valve, having main pneumaticcommutators, the commutators being interconnected to a third pneumaticcommutator interposed between the vacuum forming means and theauto-selection valve.
 2. The apparatus according to claim 1, beingessentially divided into blocks, to which at least one sucker isconnected; wherein, respectively, a first block is comprised of apneumatic installation for the supply of dependent blocks, the secondand third, comprising an auto-selector valve that interacts with vacuumgeneration means, said first block being comprised of pressureregulators and interacting commutator electro-valves with an alternativevalve; wherein said first block supplies a second block that includesthe auto-selection valve and is comprised of pneumatic commutators, arelief valve and vacuum generator means.
 3. The apparatus according toclaim 1, wherein the block having the pneumatic installation suppliesone or more suckers, just as the block that having an auto-selectorvalve that interacts with vacuum generation means is applied to everysucker or group of suckers.
 4. The apparatus according to claim 1,wherein said auto-selection valve comprises two pneumatic commutators,each provided with an axially movable and elastically yielding piston.5. The apparatus according to claim 1, wherein the circuit, in the caseof activation, through an impulse the electro-valves of the first blockare excited so that by a first electro-valve the air impulse passesthrough the pneumatic commutators of the second block to supply thevacuum generator; while with the second electro-valve, the airflowsupplies a first pneumatic commutator, in such a way as to determine themovement of the second piston; in this case the air originating from theelectro-valve, passes through the alternative valve, moves the sphereallowing the supply of the circuit, which on entering into the secondblock determines the movement of said piston.
 6. The apparatus accordingto claim 1, wherein the circuit with the airflow originating from thefirst electro-valve of the first block, entering into the subsequentblock for a few seconds, activates a depression in the circuit andtherefore maintains the piston of the pneumatic commutator inauto-relief.
 7. The apparatus according to claim 1, wherein the circuitcomprises at least one pneumatic commutator of the second block beingprovided with a more rigid spring.
 8. The apparatus according to claim1, wherein the circuit has the airflow introduced from a firstelectro-valve, passing first through the pneumatic commutators to thepiston of the second block, then through a third pneumatic commutatorprovided with a more rigid spring, to supply the vacuum generator thatraises the sphere of the relief valve thus supplying the circuit with adepression that simultaneously supplies the sucker for the movement ofthe material and the piloting of the circuit.
 9. The apparatus accordingto claim 1, wherein the piloting depression, passing through theperforations of the shaft of the piston of the first pneumaticcommutator, forms an eddy in the upper chamber of the commutatormaintaining said piston in position 0.1, forming an auto-relief circuit.10. The apparatus according to claim 1, wherein the circuit with theauto-relief function is activated when the vacuum has reached asufficient depression value to maintain the piston of the secondpneumatic commutator in raised position.
 11. Apparatus according toclaim 1, further comprising a connection between the lower chamber ofthe shaft and the upper chamber of the piston.
 12. The apparatusaccording to claim 1, wherein, in the case that the sucker should suffera substantial loss of adherence or detaches, the auto-relief of thesecond commutator of the second block is automatically de-excited,automatically interrupting the supply of the vacuum generator.
 13. Theapparatus according to claim 1, wherein in the circuit, in the stand-byphase, the first pneumatic commutator of the second block equipped witha sturdier spring than the spring of the second commutator, byincreasing depression allows the movement of the piston to the highposition, subsequently with respect to the first commutator, placing itinto the auto-relief position, in such a way as to interrupt the airfloworiginating from the first electro-valve of the first block, destined tosupply the vacuum generator.
 14. The apparatus according to claim 1,wherein during the loss of depression phase, the piston of the firstpneumatic commutator moves, placing itself in a low position, so thatthe airflow originating from the first electro-valve of the first blocksupplies the first pneumatic commutator in a high position which inturn, through the third pneumatic commutator, will supply the vacuumgenerator that re-opens the relief valve.
 15. The apparatus according toclaim 1, wherein in the circuit, the depression re-activation phasemakes provision for the circuit depression value to return to themaximum on the re-opening of the relief valve, in this wayre-positioning by auto-relief the piston of the first pneumaticcommutator to a high position and thus re-closing the compressed airfloworiginating from the first electro-valve of the first block with similarclosure of the relief valve.
 16. The apparatus according to claim 1,wherein in the circuit, the detachment phase of the sucker from thematerial, takes place continuously to maintain the first electro-valveof the first block excited and exciting a third electro-valve, whichmakes a higher air pressure flow to the circuit than the pressureflowing to the second electro-valve, thus moving the sphere of thealternative valve; the air with a higher pressure than that exerted forthe activation of the system for the adherence of the materialsmaintains the piston of the first pneumatic commutator in high position,moreover it moves the cursor of the third pneumatic commutator to a lowposition, in this way blocking the supply of the vacuum generator means,bypassing the airflow directly to the circuit to the sucker. 17.Apparatus according to claim 1, wherein the vacuum generator means ofthe type with Venturi effect are used.
 18. Circuit and apparatus thatcarries out handling with suckers, wherein a vacuum pump is providedthat supplies the circuit for the sucker detachment phase with apressurized airflow, exciting the first electro-valve and de-exciting afourth electro-valve, when for all the other previous phases the circuitis supplied by a line in depression rather than under pressure.